On Mon, Aug 11, 2025 at 6:18 PM Marie Zhussupova marievic@google.com wrote:
Add example_params_test_with_init() to illustrate how to manage shared resources across a parameterized KUnit test. This example showcases the use of the new param_init() function and its registration to a test using the KUNIT_CASE_PARAM_WITH_INIT() macro.
Additionally, the test demonstrates how to directly pass a parameter array to the parameterized test context via kunit_register_params_array() and leveraging the Resource API for shared resource management.
Signed-off-by: Marie Zhussupova marievic@google.com
Changes in v2:
- kunit_array_gen_params() is now explicitly passed to KUNIT_CASE_PARAM_WITH_INIT() to be consistent with a parameterized test being defined by the existence of the generate_params() function.
- The comments were edited to be more concise.
- The patch header was changed to reflect that this example test's intent is more aligned with showcasing using the Resource API for shared resource management.
- The comments and the commit message were changed to reflect the parameterized testing terminology. See the patch series cover letter change log for the definitions.
Hello!
Thank you for adding this example test! As before, this test looks good to me:
Reviewed-by: Rae Moar rmoar@google.com Thanks!
-Rae
lib/kunit/kunit-example-test.c | 118 +++++++++++++++++++++++++++++++++ 1 file changed, 118 insertions(+)
diff --git a/lib/kunit/kunit-example-test.c b/lib/kunit/kunit-example-test.c index 3056d6bc705d..f2819ee58965 100644 --- a/lib/kunit/kunit-example-test.c +++ b/lib/kunit/kunit-example-test.c @@ -277,6 +277,122 @@ static void example_slow_test(struct kunit *test) KUNIT_EXPECT_EQ(test, 1 + 1, 2); }
+/*
- This custom function allocates memory and sets the information we want
- stored in the kunit_resource->data field.
- */
+static int example_resource_init(struct kunit_resource *res, void *context) +{
int *info = kmalloc(sizeof(*info), GFP_KERNEL);if (!info)return -ENOMEM;*info = *(int *)context;res->data = info;return 0;+}
+/*
- This function deallocates memory for the kunit_resource->data field.
- */
+static void example_resource_free(struct kunit_resource *res) +{
kfree(res->data);+}
+/*
- This match function is invoked by kunit_find_resource() to locate
- a test resource based on certain criteria.
- */
+static bool example_resource_alloc_match(struct kunit *test,
struct kunit_resource *res,void *match_data)+{
return res->data && res->free == example_resource_free;+}
+/*
- This is an example of a function that provides a description for each of the
- parameters in a parameterized test.
- */
+static void example_param_array_get_desc(struct kunit *test, const void *p, char *desc) +{
const struct example_param *param = p;snprintf(desc, KUNIT_PARAM_DESC_SIZE,"example check if %d is less than or equal to 3", param->value);+}
+/*
- This function gets passed in the parameterized test context i.e. the
- struct kunit belonging to the parameterized test. You can use this function
- to add resources you want shared across the whole parameterized test or
- for additional setup.
- */
+static int example_param_init(struct kunit *test) +{
int ctx = 3; /* Data to be stored. */size_t arr_size = ARRAY_SIZE(example_params_array);/** This allocates a struct kunit_resource, sets its data field to* ctx, and adds it to the struct kunit's resources list. Note that* this is parameterized test managed. So, it doesn't need to have* a custom exit function to deallocation as it will get cleaned up at* the end of the parameterized test.*/void *data = kunit_alloc_resource(test, example_resource_init, example_resource_free,GFP_KERNEL, &ctx);if (!data)return -ENOMEM;/** Pass the parameter array information to the parameterized test context* struct kunit. Note that you will need to provide kunit_array_gen_params()* as the generator function to KUNIT_CASE_PARAM_WITH_INIT() when registering* a parameter array this route.** Alternatively, since this is a static array we can also use* KUNIT_CASE_PARAM_ARRAY(,DESC) to create a `*_gen_params()` function* and pass that to KUNIT_CASE_PARAM_WITH_INIT() instead of registering* the parameter array here.*/kunit_register_params_array(test, example_params_array, arr_size,example_param_array_get_desc);return 0;+}
+/*
- This is an example of a test that uses shared resources available in the
- parameterized test context.
- */
+static void example_params_test_with_init(struct kunit *test) +{
int threshold;struct kunit_resource *res;const struct example_param *param = test->param_value;/* By design, param pointer will not be NULL. */KUNIT_ASSERT_NOT_NULL(test, param);/** Here we pass test->parent to search for shared resources in the* parameterized test context.*/res = kunit_find_resource(test->parent, example_resource_alloc_match, NULL);KUNIT_ASSERT_NOT_NULL(test, res);/* Since kunit_resource->data is a void pointer we need to typecast it. */threshold = *((int *)res->data);/* Assert that the parameter is less than or equal to a certain threshold. */KUNIT_ASSERT_LE(test, param->value, threshold);/* This decreases the reference count after calling kunit_find_resource(). */kunit_put_resource(res);+}
/*
- Here we make a list of all the test cases we want to add to the test suite
- below.
@@ -296,6 +412,8 @@ static struct kunit_case example_test_cases[] = { KUNIT_CASE(example_static_stub_using_fn_ptr_test), KUNIT_CASE(example_priv_test), KUNIT_CASE_PARAM(example_params_test, example_gen_params),
KUNIT_CASE_PARAM_WITH_INIT(example_params_test_with_init, kunit_array_gen_params,example_param_init, NULL), KUNIT_CASE_SLOW(example_slow_test), {}};
2.51.0.rc0.205.g4a044479a3-goog